rumble from the front

ok, now i have the attention of the free world, i have a question.

i swaped the front axle out of my 85XJ for a newer D30 ( i dont know the year of the donor ) and had to use the rotors off the 85 axle and they didnt seem to want to fit right but with a little purswasion they went on but now i have a rumble, a really loud and BAD rumble from the front, ideas of what it is and fixes are welcomed and asked for.

i was told the older rotors were just slightly different than the newer ones, this being ( i assume ) true, and the cause of the rumble,should i buy new rotors? $21 a piece but the old rotors are in excelent condition.

should i put the pepboys 1/4 inch spacers behind the rotor and go with it? this would alow the rotors to sit evenly on the hub, all be it a quarter inch from where they are supposed to be.

should i swap out the hubs and keep the rotors and hubs matched, this is a little more work but it is the cheapest option. ( two cotter keys and some time )

these are what i have so far and i wanted the ideas of you wise and knowledgable :: XJ mech types.

thanks.

steagall9301 said:

ok, now i have the attention of the free world, i have a question.

i swaped the front axle out of my 85XJ for a newer D30 ( i dont know the year of the donor ) and had to use the rotors off the 85 axle and they didnt seem to want to fit right but with a little purswasion they went on but now i have a rumble, a really loud and BAD rumble from the front, ideas of what it is and fixes are welcomed and asked for.

i was told the older rotors were just slightly different than the newer ones, this being ( i assume ) true, and the cause of the rumble,should i buy new rotors? $21 a piece but the old rotors are in excelent condition.

should i put the pepboys 1/4 inch spacers behind the rotor and go with it? this would alow the rotors to sit evenly on the hub, all be it a quarter inch from where they are supposed to be.

should i swap out the hubs and keep the rotors and hubs matched, this is a little more work but it is the cheapest option. ( two cotter keys and some time )

these are what i have so far and i wanted the ideas of you wise and knowledgable :: XJ mech types.

thanks.

Click to expand...

Ther really are several variants of hubs and rotors, depending largely on whether or not the hubs are cast iron or composite (steel center). It would help a great deal if you knew the year of the donor, but if your new axle is a "non-disconnect" type from somewhere in the early to mid 90's, it's probably got composite rotors. I believe they went back to a cast rotor in the last few years, but that the dimensions were not the same as the original cast rotors. I think your best bet is new rotors of the right type. I'm not entirely sure that the brake caliper brackets are amenable to swapping in a different type hub and rotor. They might be, but why take the chance, especially if the hubs are good, but rusted into the knuckles as they often are? I'd go for the correct rotors for the existing hubs and caliper brackets.

Take a look at the rotors you do have, which do not fit right. You can measure them and figure out how much difference you need. You can also figure out often whether or not they are cast or composite. If you think of the rotor as a hat, the top of the hat will be rounded if they are composite, and sharp-edged if they are cast. If you now have cast rotors, you probably need the composite.

by the way, they are both disco axles if that helps